Three new rape victims arrive each day at the Rape Crisis Treatment Center in Santa Monica, Calif., where, besides being given comfort and medical care, victims are offered a forensic examination that could help identify and prosecute their attackers. Seeing the pain of the victims is hard enough, but for the center’s director, Gail Abarbanel, one of the worst parts of her job is wondering whether rapes could have been prevented had the evidence so painstakingly collected ever been tested.

All over the country, rape kits are sitting untested in refrigerated storage facilities. A report compiled by Human Rights Watch (HRW) puts the number at over 400,000, and the backlog is particularly pressing in large urban centers like Los Angeles. For Abarbanel, it represents a profound betrayal. “When such an incredible tool as a forensic database is available to us, it is unforgivable not to make use of it,” she says. “For every kit that is not tested, the possibility of identifying, apprehending, trying and prosecuting a violent offender is lost.”

Rape kits lie untested in Los Angeles and other cities exist despite generous federal funding under the Debbie Smith DNA Backlog Grant Program. Named for a rape victim whose assailant wasn’t apprehended for six years while Smith’s rape kit lay untested, the program provided $43 million to state crime labs in 2007. Yet California, along with 16 other states, had its grant slashed by 50 percent last fiscal year—a funding loss of $500,000—because it was failing to make proper use of the monies.

Sarah Tofte, the lead rape-kit researcher at HRW, points to New York as an example of how, with political leadership and a clear strategy, police can clear a backlog—in this case, within three years—and not let it build up again. And the results can be stunning: When the New York Police Department processed 16,000 untested kits, it found over 2,000 hits on the DNA database, leading to around 200 arrests.